1. Field of the Invention
The present invention generally relates to an apparatus and method for driving and adjusting light, and more specifically to an apparatus and method for driving and adjusting light of light-emitting diode (LED) lighting device, without the necessity to change the existing wiring or the structure of the lighting device, to change the lighting by counting the number of switching ON/OFF times so that the LED driver has the light-adjustment capability and the lighting of the LED lighting device is adjustable.
2. The Prior Arts
As the environmental consciousness increases and the energy consumption awareness becomes an agenda, the LED lighting devices gain popularity because of the superior energy efficiency in comparison with the conventional incandescent lamps and fluorescent lighting devices. Therefore, LED is replacing the conventional incandescent or fluorescent bulbs in many lighting devices. However, while LED is more energy efficient, the existing switches and the lighting devices only allow the ON/OFF options for the LED. In other words, the existing switches and lighting devices do not support light adjustment when using LEDs.
At present, the LED driver design focuses on how the LED driver keeps the LED in stable brightness when the input voltage changes. The disadvantage is that additional control signals are required for LED light adjustment; therefore, with the restrictions of the existing wiring, the structure of lighting device and light adjustment device, it is difficult to provide light adjustment for LED because this may imply re-wiring and purchase of new lighting device and light adjustment device. Therefore, LED lighting device is still unable to replace the existing lighting devices.
As for the current fluorescent lighting device, because the fluorescent tube is not adjustable and allows only ON/OFF states, the light adjustment is achieved by switching on different numbers of fluorescent tubes so as to achieve different brightness. However, the above approach usually leads to non-uniform light distribution. In addition, the above approach is also restricted by the number of the fluorescent tubes and the number of the combinations available on the lighting device. When the fluorescent tube is damaged, the options for light adjustment are further restricted. Hence, it remains an important issue in the LED driver design to replace the existing lighting with the LED without the necessity to change the existing wiring or the structure of the lighting device so that the LED light can be adjusted in addition to the lighting capability.